1. Field of the Invention
This invention relates to a novel catalyst system for the polymerization of alpha-olefins, a novel titanium halide containing catalyst component used in said system, a process for producing said component and a process for the polymerization of alpha-olefins using such catalyst system.
2. Prior Art
The polymerization of alpha-olefins in the presence of a catalyst system comprising: (a) an organoaluminum containing component, and (b) a titanium halide containing component is well known in the art and the polymers produced utilizing such catalyst systems have found numerous uses. The resulting crystalline polymers have associated therewith, to a greater or lesser degree, a low molecular weight amorphous polymer. The production of polymers having a low concentration of such amorphous polymers results in a polymer having highly desirable properties. The production of highly stereoregular crystalline polymers is thus a desirable objective for a catalyst system and polymerization process.
It is also desirable that high amounts of polymer be produced per unit of time per unit of catalyst employed, i.e. the catalyst system have a high activity. Ideally, it is highly desirable to simultaneously improve the stereospecificity and activity of a catalyst system.
Various approaches to achieving the aforementioned objectives have been proposed in the art.
South African Pat. No. 78/1023 to Toyota et al. describes producing a titanium halide containing component by reacting a mechanically pulverized product of an organic acid ester and a halogen containing magnesium compound, with an active hydrogen containing organic compound in the absence of mechanical pulverization. The resulting reaction product is then reacted with an organometallic compound of a metal of Groups I to III of the Periodic Table in the absence of mechanical pulverization. The resulting solid reaction product is then washed with an inert organic solvent, and the resultant solid reacted with a titanium compound in the absence of mechanical pulverization. The resultant solids are then separated from the reaction system. This reference, however, does not teach copulverizing the halogen containing magnesium compound with an active hydrogen containing organic compound, nor copulverizing with a complex of a titanium halide compound and an electron donor prior to reacting with the titanium compound.
U.S. Pat. No. 4,149,990 to Giannini et al. describes a titanium halide containing component obtained by reacting a halogenated titanium compound with the reaction product of a magnesium dihalide, an electron donor compound and an organometallic compound and an electron donor free of active hydrogen atoms. The later electron donor may be reacted with the titanium compound prior to reacting with the magnesium dihalide containing product. This reference does not describe further reacting the product with a titanium halide compound nor copulverizing with a complex of a titanium halide compound and an electron donor prior to reacting with such titanium halide compound.
U.S. Pat. No. 4,076,924 to Toyota et al. describes a titanium halide containing component obtained by reacting a solid magnesium component with a liquid or solid titanium compound, the solid magnesium component being obtained by a reaction product derived from a magnesium dihalide, an alcohol, an organic acid ester and an organometallic compound. This references does not teach the use of phenol, applicant's preferred active hydrogen containing organic compound, copulverizing with a complex of titanium halide and an electron donor nor the final reacting of the product with a titanium halide compound.
Of additional interest is U.S. Pat. No. 4,143,223 to Toyota et al. which describes reacting a mechanically copulverized solid component of, for example, magnesium chloride, an organic acid ester and an active hydrogen containing compound, e.g. phenol, with a tetravalent titanium compound, e.g. TiCl.sub.4. This reference does not teach reacting with an organometallic compound.